Neuropixels

To understand how the brain operates, we must measure and influence the activity of a myriad individual neurons distributed across brain regions. Until recently, this had been impossible: recording methods could either resolve the activity of individual neurons or monitor multiple brain regions. Starting in 2017, Neuropixels probes have made it possible, by packing about 1,000 recording sites spaced only 20 μm apart over a one-centimeter shank.

Neuropixels constitute a step advance in recording technology. Thanks to their dense and numerous recording sites, and their extremely low noise levels, they allow superior discrimination of the spikes of individual neurons. Their success is due to three innovations: (1) a multilayer fabrication process that allows hundreds of recording channels on a thin shank; (2) on-shank CMOS circuitry that allows those channels to be rapidly allocated to a subset of thousands of sites; (3) on-device processing that amplifies, digitizes, and multiplexes the signals. Neuropixels thus constitute a self-contained recording system: the data that emerge are already digital, and can be read by a simple, inexpensive interface to a standard computer.

Since the first version, called Neuropixels 1.0, multiple versions of the probes have been designed, tested, and released. Announced in 2021, Neuropixels 2.0 probes had smaller dimensions and provided 4 shanks, increasing the scale of recordings and facilitating recordings during free movement. They allowed experimenters to record from the same neurons for weeks or even months.  Other versions include Neuropixels NHP, and Neuropixels Ultra, both announced in 2023. Neuropixels NHP probes provide longer shanks for use in primates including (in certain highly controlled conditions) human patients. Neuropixels Ultra probes allow denser sampling to improve detection, yield, and cell type specificity of brain recordings. 

In 2025, a new type of probe was announced called Neuropixels Opto. This probe combines high-resolution electrophysiology and optogenetics. 

Neuropixels probes are designed and fabricated by IMEC, the nonprofit nanoelectronics research center. Testing and applications of the probes are performed by neuroscientists at multiple institutions including University College London. The probes are available at cost price from neuropixels.org.